In Heidegger's own words, when the being of something is to be determined through inquiry, the being which is to be determined is “in a certain way already understood.” It exists as a “preunderstanding” that is given to one even if it exists as “unoriented and vague preunderstanding.” [Pp. 143-4]. While Lonergan speaks about an a priori notion of being that is purely heuristic and which is without any kind of conceptual or formal content (“notion of being” versus “concept of being”), in Heidegger's notion of being, various texts here and there refer to a prior understanding of being which is already given and operative in human inquiry and which is not to be confused with determinate anticipations of being which exist either as assumptions, or as prejudices, or as prior understandings in the context of a particular inquiry which is seeking to solve a problem or to move toward some degree of growth in the content of one's understanding.

Haven't philosophers identified such a pre-understanding with the qualifier "arche"?

Levinas, as I understand him, contests MH's assertion that the ultimate "ante" is an understanding of beyng by identifying it instead as the ethical claim of responsibility on us for the wholly other person. At that reach, it is beyond verification.

a prior understanding of being which is already given and operative in human inquiry

Perhaps, but the discussion won't likely go very far with "already givens" will it. Some may still have that problem with Kant (not to say PoMo)-- if you accept say the first 50 pages or so of the 1st Kritik, yll probably buy the entire schema. But for those Diogenes-types who can't quite buy the synthetic a priori (or rather, who don't find a necessary argument, or even cogent one, apart from...there are cognitive givens of some type) they probably won't

Verification, or evidentialism as it was formerly known definitely has limitations--not sure they outnumber those of the non-verificationists, ontologists, conceptualists, etc

Somewhere MH refers (and for all my recent hunting, I cannot seem to find my way to it) Aristotle's reference to what is obvious and taken for granted. MH adds the example of "red" as I recall. It's something that does not demand proof.

Similarly Aristotle's logic of non-contradiction. I have been told logicians are constructing systems without that requirement.

It's been a while since I read Popper and Quine but don't they point out that "givens" cannot be avoided?

J writes, "So how do we...prove the synthetic a priori-claim true or false?"

When I saw Kant's proof, it was more than I could comprehend. As best I can understand it, he appeals to the analogy of math. However, the prof told us the synthetic apriori really doesn't hold up. And since Kant's assumptions about subjectivity are open to question, that seems to me a more significant complait.

Yet in my on-going study, I find a repeated appeal to the transcendental dimension of whatever subject matter is at issue. So Kant's strategy continues to influence.

that said, I understand the.......anti-rationalist impulse, Miss Jan.--just tend to read it in Nietzschean terms (via some Darwin & Co as well), rather than "ontology"/Heidegger. Nietzsche loved Heraclitus as well doesn't he. Yet...living dangerously. Well. the Raubtier's got issues. Actually I don't completely disagree with some ...leftists who consider Nietzsche (and...perhaps Heidegger in a different sense) culpable to some degree for 20th century nihilism (tho more because of their ideas in the wrong paws, than bio-factors).

As best I can understand it, he appeals to the analogy of math. However, the prof told us the synthetic apriori really doesn't hold up.

as you probably know, the analytical school claimed, contra Kant, that mathematics was analytic a priori (so..transcendence, tho of a more platonic variety may be still possible--....the naturalist/nominalist must confront Frege etc). There were no synthetic a priori statements, according to those nasty positivists--just analytical a priori and synthetic a posteriori (ie natural sciences, social sciences, etc).

While dislikng those logic choppers as much as anyone, mathematics..and logic (like, the law of non-contradiction, and excluded middle) has a certain elegance. Kant's conception IIRC related to Time and has all sorts of metaphysical baggage.

And one might say....what category do ontological/metaphysical claims fall under?/ They are not analytical, IMHE. So synthetic? (or meaningless for Carnap). I understand a need for foundations of a sort, but...its an interesting question

correctio (writing w/o sufficient caffiene)---While disliking those logic choppers about as much as anyone, the analytical-a priori view of mathematical..and logical identities (like, the law of non-contradiction, and excluded middle) has a certain elegance, even if one grants ala Quine ...in the long haul (like, evolutionary POV) the definitions/identities might change/ be altered. Call that pragmatic analyticity IYW